From: Pablo Neira Ayuso <pablo@netfilter.org> stable inclusion from linux-4.19.198 commit 3225cd78880a15928f8930e3de698a6edca63f42 -------------------------------- [ Upstream commit 8f518d43f89ae00b9cf5460e10b91694944ca1a8 ] The osf expression only supports for TCP packets, add a upfront sanity check to skip packet parsing if this is not a TCP packet. Fixes: b96af92d6eaf ("netfilter: nf_tables: implement Passive OS fingerprint module in nft_osf") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- net/netfilter/nft_osf.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c index a003533ff4d93..e259454b6a643 100644 --- a/net/netfilter/nft_osf.c +++ b/net/netfilter/nft_osf.c @@ -22,6 +22,11 @@ static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs, struct tcphdr _tcph; const char *os_name; + if (pkt->tprot != IPPROTO_TCP) { + regs->verdict.code = NFT_BREAK; + return; + } + tcp = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(struct tcphdr), &_tcph); if (!tcp) { -- 2.25.1